ANTLR is a powerful parser generator for multiple programming languages including Java.

ANTLR contains 2 major modules:

• Runtime - For building and executing parsers/lexers generated in Java.
• Tool (The Parser Generator) - For generating parsers/lexers Java class.

ANTLR Tool Source Code files are provided in the distribution packge (antlr4-4.10.1.zip). You can download them at ANTLR Website.

You can also browse the source code below:

⏎ org/antlr/v4/codegen/model/OutputFile.java

/*
 * Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
 * Use of this file is governed by the BSD 3-clause license that
 * can be found in the LICENSE.txt file in the project root.
 */

package org.antlr.v4.codegen.model;

import org.antlr.v4.Tool;
import org.antlr.v4.codegen.OutputModelFactory;
import org.antlr.v4.tool.Grammar;
import org.antlr.v4.tool.ast.ActionAST;

import java.util.HashMap;
import java.util.Map;

public abstract class OutputFile extends OutputModelObject {
	public final String fileName;
	public final String grammarFileName;
	public final String ANTLRVersion;
    public final String TokenLabelType;
    public final String InputSymbolType;

    public OutputFile(OutputModelFactory factory, String fileName) {
        super(factory);
        this.fileName = fileName;
        Grammar g = factory.getGrammar();
		grammarFileName = g.fileName;
		ANTLRVersion = Tool.VERSION;
        TokenLabelType = g.getOptionString("TokenLabelType");
        InputSymbolType = TokenLabelType;
    }

	public Map<String, Action> buildNamedActions(Grammar g) {
		Map<String, Action> namedActions = new HashMap<String, Action>();
		for (String name : g.namedActions.keySet()) {
			ActionAST ast = g.namedActions.get(name);
			namedActions.put(name, new Action(factory, ast));
		}
		return namedActions;
	}
}

⏎ org/antlr/v4/codegen/model/OutputFile.java

Or download all of them as a single archive file:

File name: antlr-tool-4.10.1-sources.jar
File size: 347718 bytes
Release date: 2022-04-15
Download 

⇒ Donwload antlr4-4.10.1.zip

⇐ ANTLR Runtime Source Code

⇑ Download and Review ANTLR Parser Generator

⇑⇑ FAQ for ANTLR Parser Generator